(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A student standing on top of a cliff drops a rock down below into the water and hears it splash 3 seconds later. The speed of sound is 330m/s, what is the height of the cliff

2. Relevant equations

v= d/t

v2 = v1 + at

d = v2-1/2 at2

d = (v1 + v2)t

v2 squared = v1 squared + 2ad

d = v1t + at2

3. The attempt at a solution

when I first saw this, I thought of echos

v=d/t

330 = d/3

d=990

and then divide by two since echo

d= 990/2

d= 495

however, that is horizontal distance not vertical, so I listed my knowns but am unsure as what to do with the 330 m/s

knowns for rock

v1= 0 (since he dropped the rock)

v2=

a = -9.8 m/s2

t = 3s

d =

knowns for speed of sounds

v= 330 m/s

t = 3s

d= ?

then setting the distance of both of these equal to each other and solving for d?

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# Homework Help: Linear Motion: calculating height of cliff given speed of sound and time

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